An operator of a furnace may have to know the furnace internal conditions in order to control furnace settings and/or to achieve a threshold efficiency. For instance, an accurate understanding and/or estimate of an intensity of a flame in the furnace can be used to determine if the combustion process of the furnace is operating appropriately. A flame scanner can be used to monitor the combustion process of a furnace to provide a signal indicating the intensity of a flame in the furnace.
An objective of monitoring a combustion process can be to monitor the process and avoid instabilities of the flame. For instance, the monitoring of the combustion process can improve system performance, reduce levels of harmful emissions, and/or extend the stability domain by reducing oscillations induced by coupling between resonance modes and combustion, among other benefits.
Conventional flame scanners may produce an electrical signal based upon a monitored flame. This electrical signal can be transmitted to processing electronics that are housed separately from the flame scanner. Such flame scanners typically scan light emitted in a fixed wavelength range.
In some instances, however, furnaces, such as industrial furnaces, can have combustion processes that produce flames at a variety of wavelength ranges. For example, the wavelength range of the flame that is monitored may change depending on the particular time of day and/or combustion process being performed.